In order to avoid the complexity and expense of individual wiring of organ keyboards it has become known to utilize multiplexing of the keyboard, see for example Watson U.S. Pat. No. 3,610,799. A serial data stream is thus generated with pulses in the serial data stream indicating which notes are to be played. Other information also may be carried such as the condition of various controls including the position of stop tablets. The pulses in the serial data stream provide information to electronic tone generating circuitry to effect production of tones corresponding to keys that are depressed on the keyboard to close corresponding keyswitches.
The production of transposition by selectively delaying the serial data stream also is known as disclosed in Deutsch U.S. Pat. No. 3,610,800.